The instant invention relates to the filling of a flat can with fiber sliver by a textile machine which delivers a fiber sliver, such as a carding machine or draw frame, whereby the flat can is moved beneath a rotary plate rotating in one place. The movement of the can influences the quality of the deposited fiber sliver and the degree of can fullness.
According to the state of the art, flat cans are filled in that a rotary plate functioning as a delivery device rotates in one place, the flat can being moved back and forth beneath this rotary plate. In other words, the flat can is traversed below the rotary plate. During the traversing of the flat can its speed is synchronized with the delivery speed of the fiber sliver. The back-and-forth movements of the flat can are carried out at a constant speed as far as the reversal point. In executing this movement, the flat can together with its supporting surface assumes an even position.
In order to attain a higher degree of can fullness with a defined quality of fiber sliver to be deposited, it was proposed in the state of the art (compare EP 457 099, column 4, 26th to 33rd line) to combine the straight-line traversing movement of the flat can with a lateral transversal movement. EP 457 099, column 12, lines 35-39 assumes that the lateral, translational transversal shifting of the flat can is able to increase the degree of fullness by shifting the loop deposit of the fiber sliver. This fact is significant since the can serves at the same time as a buffer storage between draw frame and rotor spinning machine so that its transportation frequency decreases as the degree of fullness increases. EP 457 099, column 4, lines 26-31 proposes in this context that the flat can be shifted by a lateral transversal movement upon passing the respective cuspidal point, whereby the shifting distance is approximately equal to the thickness of a fiber sliver. The document (EP 457 099, column 12, lines 39-42) gives no information concerning technological feasibility, but according to the state of the art the utilization of rail-travelling carriages (DE-OS 19 23 621) is possible in order to traverse the flat can as well as to enable the appertaining lateral transversal shifting.
DE-OS 19 32 621 describes how the transversal shift is carried out by two conveying devices (upper carriage and lower carriage) controlled independently of each other. The long can is here standing on the upper carriage. The directions of movement between the lower carriage and the upper carriage are arranged so that they can be executed at a right angle to each other. The lower carriage carries out the traversing movement and the upper carriage carries out the straight-line, lateral transversal shift of the flat can. In this document, it is stated that the two directions of movement are to be superimposed so that a resultant direction of movement follows.
It is characteristic for these solutions of the state of the art that the lateral shift of the flat can is a translational motion. This translational lateral shift of the flat can is obtained at a relatively high cost. The disadvantageous cost is due to the additional two carriages and to their control. It is a disadvantage here that the inert mass to be moved increases unnecessarily.
As the degree of fullness of the flat can increases, the problem of inertia forces being produced together with the translational lateral shift further arises, the inertia forces having to be absorbed by the flat can and the traversing apparatus. This requires correspondingly large dimensions of the flat can and of the traversing apparatus, which results in higher costs.